1. Field of the Invention
The present invention relates to a biopsy apparatus for inserting a biopsy needle into an object to be examined in a living body such as a human body or the like, and sampling tissue from a biopsy region in the object to be examined. The present invention also is concerned with a spatial range measuring apparatus and a spatial range measuring method for measuring a spatial range within which the biopsy needle can extract tissue from the biopsy region. The present invention further relates to a phantom for use in training doctors to perform a biopsy procedure, and for measuring a spatial range within which a biopsy needle can sample tissue from a biopsy region.
2. Description of the Related Art
Heretofore, biopsies have been performed in clinical medicine to enable a doctor to sample tissue from a biopsy region in an object to be examined in a living body such as a human body by inserting a biopsy needle into the object to be examined. Generally, it is difficult for the doctor to visually recognize the biopsy region in an object to be examined, such as a lesion in the breast. According to such a biopsy procedure, a stereoscopic image capturing process is carried out on an object to be examined by applying radiation to the object to be examined, thereby acquiring a stereoscopic image of the object to be examined. Then, a three-dimensional coordinate position of a biopsy region in the object to be examined is calculated, and the doctor inserts a biopsy needle into the object to be examined based on the calculated three-dimensional coordinate position. Tissue then is sampled from the biopsy region through the biopsy needle.
According to the biopsy procedure, it is preferable to insert the biopsy needle into the biopsy region without causing significant damage to the living body, and to sample tissue from the biopsy region reliably and accurately, upon undertaking efforts to sample tissue from a biopsy region which is difficult to visually recognize from outside of the living body. Recent years have seen the development of a phantom, which simulates an object to be examined in a human body and tissue of a biopsy region, with a view to improving the skill of doctors who carry out biopsy procedures (see, for example, U.S. Pat. No. 5,273,435).
The phantom disclosed in U.S. Pat. No. 5,273,435 includes a gelatin body in the shape of a compressed human breast, and a plurality of simulated tumors contained within the gelatin body. The simulated tumors are made of a radiopaque material of iodinated oil (black pigment). The gelatin is permeable to X-rays and light. The black pigment is impermeable to light. The phantom is used in the following manner. A trainee, e.g., a doctor, inserts a biopsy needle into the phantom and extracts, as a sample, the black pigment from one of the stimulated tumors along with a portion of the gelatin in the vicinity of the black pigment. Then, the trainee pulls out the biopsy needle in order to remove the sample. In this manner, using the phantom, the trainee is trained to perform a biopsy procedure.